Pipe organ for producing a piano effect



April a, 1928. 1,664,554 J. H. HAMMOND, JR

PIPE ORGAN FOR PRODUCING A PIANO EFFECT F d Aug 17, 1925 2 Sheets-Sheet 1 INVENTOR H [3 ATTORNEY Apfil 3, 1928.

' 1,664,554 J. H. HAMMOND, JR

PIPE ORGAN FOR PRODUCING A PIANO EFFECT Filed Aug. 17. 1925 2 Sheets-Shut 2 INVENTOR Patented Apr. 3, 1928.

UNITED STATES JOHN HAYS HAMMOND, JR, 0.! GLOUQESK KEB, MA$ACHUSETTS.

PIPE O GAN FOR PRODUCING A PIANO EFFECT.

Application filed August 17, 1925. Serial No. 50,688.

This invention relates to improvements in musical instruments and more particularly ,to improved means to be applied to pipe organs whereby piano effects may be readily produced.

In playing a pipe organ of the ordinary type, it is difficult to emphasize the melodic phrasing of the music without sacrificing at least some of the notes of the accompaniment. It is usual to emphasize the melody by playing it on a manual or register actuating a portion of the organ of relatively intense tone, the accompaniment being confined to other manuals and .being played more subdued. This usually requires an entire hand of the operator to be devoted to the solo part or melody, and thus limiting the number of notes which can be played simultaneously by the operator.

In piano playing, however, the melody can readily ,be emphasized by distinctive finger action. The finger which plays the note of the melody strikes the key with greater speed than .is employed in connection with the remaining keys.

A principal object of the invention is to provide improved means whereby this piano effect may be employed on a pipe organ, thereby simplifying the emphasizing of the melody.

Other objects are to provide means ;f o r varying the volume of sound emitted from a pipe or group of pipes corresponding to a given note; to provide means for permitting the full volume of sound produced-by a ,pipe or group of pipes to have an nltial "maximum which will gradually dimmish at a given rate; to provide means for causing this initial maximum to be proportional to the force with which the corresponding key is struck; to provide means for causing the quality of a note to be (changed in a predetermined manner according to the force with which thecorres ponding key is struck;

and to provide other improvements as will hereinafter appear.

In the-accompanying drawing, Figure 1 is diagrammatic view, partly in section, of

.one form of the invention, as applied to a pipe organ.

Figure 2 is a diagrammatic view of a modified form .of the invention shown in Figure 1.

Referring to F gure 1 01' vthe accompany- ,ing drawings, in which there is shown so muclrof a pipeorgan as 18 necessary to an understanding of one form of the invention,

the pipe organ includes an organ chamber 10 in which-there is mounted a wind chest 11 of well known construction. The chest 11 carries a plurality of groups of pipes, each group corresponding to a certain stop, as for example, the oboe, -flute, etc. The pipes illustrated in the drawings are understood to correspond'to pipes-tuned to the same note of a musical scale, as for example, middle C, each being associated with a d fferently characterized stop. Four stop pipes are shown designated respectively 13, 1a, 15 and 16. It is understood that the p pes corresponding to each note of a scale are contained in a separate compartment, such as shown, the apparatus and equipment beitng duplicated for each such additional no e.

For varying the intensity of sound emitted from the groups of pipes corresponding to a given note there is provided in connection with each respective compartment a set of swell shutters 17, 17 which are pivotally mounted in alignment to form when closed .one wall of the chamber 10. The several shutters of each compartment are operatively interconnected by a link 18 and are normally held in closed position by means of a. retractile spring 19 interconnecting the link 18 to a fixed portion of the chamber 10. One end of thelink 18 is pivotally connected by means of a connecting link 20 to I of the battery 31 is connected to a contact 32 supported in a fixed frame work 33 and presses against a square rod 34 of insulating material. The rod 34 has affixed thereto a pair of strips of conducting material 35, 36

and is slidably mountedupon a pair of brackets 37 ,38 afiixed to the frame '33 so as to slide longitudinally therein. Mounted in spaced relation with each other and with the contact 32 is a plurality of contact springs 40, 41, 42, 43, and L4 which are .mounted upon the frame 33 in any suitable manner, the :free ends of which press against the movable rod 34. The contacts 40, 11, 42, 4:3 and 44. are electrically connected to the terminals 25, 26, 27, 28 and 29 respectively. B or actuating the primary action of the wind chest 11 there is provided a circuit including a source of energy,such as a battery 49 and conductors 17, 48 extending to the contact springs 45, e16 respectively. The contact springs 45 46 are mounted in spaced relation upon the frame 33 and'insulated therefrom and from each other; in the non real position of the rod 3%, as illustrated, the conducting segments 35, 36 are in such position that the circuits, including thebatteries 31 and as respectively, are open and these circuits are, only closed when the rod 84 is moved longitudinally as will be subsequently set forth. I

For moving the arm 34 there is provided a floating lcver o0 having a slot 51 engaginga pin 52 attired to one end oi the rod 34-. The lever .ispivotally connected at a fulcrum 53 intermediate its length to a rod fi l extending substantially parallel to the rod 34. The lever 50 is provided at its other end with a slot 56 similar to the slot 51. The slot 55 engages pin 56 rigidly secured to a movable solenoid. core 5?. Suitable guides 59, 59are proviided tor the rod 54L- and the so lenoid core 57 to permit the respective, longitudinal movement thereof. The rod 54 and core 57 are normally maintained in the position shown by meansol' retract-lie springs 58 and 60 alliired to oneend of the cores 57 and 5d and to a portion of the frame work of the organ.

For controlling the movement of the rod 54 there is provided therein a pin 61 in the path or? movement of a linger 62. The linger 62 is pivotallysupported upon one arm 63 o l a bell-crank lever 64-, the other arm 65 of which forms the arr ature or an electro-magnet 66. Aqretractile spring 68 provided for maintaining the bell-crank lever 6 in the position lllt ted. The bell-crank lever 64; is pivotally's .pported in well known manner upon a fixed bracket extending outwardly from the frame of the electro-magnet 66. The linger 62 is provided with a lug 7 0 and the bell-crank lever 64 is providedwith an oppositely positioned like lug 71, there being interposed between thelug 70 and 71v a retractile spring 67 for normally maintaining the finger 62 in the position shown. The linger 62 is provided with a stop member is integral. therewith and arranged to engage the arm 63 to limit the retractile movement of the finger 62 relative to the arm 63.

For retarding the movement of the rod 54 in one direction and for causing it to move ata predetermined speed after a working stroke, there is provided at its free end a piston 73 rigidly secured to a rod The piston 7 is arranged to slide in a fixed dash pot casing 74, the cylinder oi": which is opened nee area at one end to allow unrestricted movement of the piston 73 during a working stroke of closed by a valve connected to and operated by an armature 65 ot' the magnet 66. The opposed end of the passage 75 is controlled by an adjustable needle valve 81 of usual construction, the position of which with respect to the passage 75 determines the rate at which the air escapes from the cylinder of the dash pot 74-. The piston 73 is closely titted within the cylinder and move-- mentthereoi in one direction is greatly restricted by the flow of air by the needle valve 81. i V

For energizing the magnet 66 there is provided a circuit including a source of energy such as abattery 83,'one pole oi. which is connected by means of a conductor 82 to one terminal of the winding of the magnet 66. The'other pole of the battery 83 is connected by a conductor 84 to a brush eontactor 85 co-operating with a fixed contact 86 which in turn is connected by a conductor 87 to the other terminal of the winding of the magnet 66. The brush contractor 85 is fixed to and carried by a movable organ key 90 pivotally mounted at 91 and 1naintained in normal position by a retractile spring 92,.the retractile spring being attached to a fixed member 93' secured to a. portion of the frame work of the organ.

The member 93 also serves as a stop member to limit the movement of the key 90. The arrangement is such that upon depression of the key 90 contact is closed between the contactor 85 and the contact 86 to close the circuit of the magnet 66. Thus the magnet 66 is energized to oscillate the bell-crank lever 64.. i V

In order to limit the downward movement of the arm 3 1 so that its stroke is varied in accordance with the speed at which the key 9O depressed, the core 57 is arranged to be actuated'by a solenoid 95, one side of the winding of which is connected by a conducloo opposite end pivoted at 112 to an extension 113 of the key 90. This extension 113 serves as a support at 114 for the arm 111, and has a toothed member 115 pivoted thereon and projecting upwardly in the path of a pin 116 on the arm 111. A spring 117 tends to rotate the member 115 counter-clockwise and thus holds the toothed part in position to engage the pin 116 when the arm 111 is swun in a clockwise direction by the depression of the key 90. A pin 118 secured to a fixed part is provided which engages the toothed member 115 when the key 90 is in the position shown thus releasing the pin 116.

In the operation of this invention shown in Fig. 1, when it is desired to sound the group of pipes 13, 14, 15 and 16, the key 90 is depressed, and the speed at which it is depressed determines the relative position which the weight 110 will assume. Thus, it the key 90 is depressed gently, the weight 110 will not change its position with respect to the key 90 and the contactor 107 will rest on the segment 100 when the key 90 is fully depressed. If, however, the key 90 is depressed with greater speed, the momentum of the Weight 110 will cause it to over-run the position of thekey 90, thus moving the contactor 107 into engagement with the segment 101. It will thus be seen that the contactor 107 will engage one of the segments 100-to 103, depending upon how fast the key '90 is depressed. When the key 90 is released and assumes the position shown in Fig. 1, under the action of the spring 92, the pin 118 will engage the member 115 and thus cause it to release the pin 116 which will allow the arm 111 and the weight 110 to as sume their initial positions, as shown in Fig. 1, under the action of gravity. Suppose, for example, that the key .90 has been depressed with sufficient speed to cause the contactor 107 to make contact with the segment 101. This will cause a current to flow from the battery 83 through the conductors 84 and 108, contactor 107, segment 101, resistance 104, segment 100, conductor 97 and solenoid -95, conductors 96 and 82, back to the battery 83. This causes a definite amount of current to pass through the solenoid 95 and causes the core 57 to assume a definite position dependent upon the strength of this current and upon the strength of the spring 58. The pin 56 and therefore the left-hand end of the lever 50 will be moved into and held in a definiteposition. When the key '90 is depressed, the contactor 85 engages the contact 86, thus closing the circuit through the magnet 66, which attracts the bell-crank lever 64, rotating it about its pivot in a counter-clockwise direction. This causes the finger 62 to engage the pin 61, thus moving the .rod 54 and the piston 73 downwardly.

This motion is very rapid, as air enters the check valve 77. Before the bell-crank lever 64 has reached the end of its motion, .the finger 62 has slipped out of engagement with the pin 61, thus allowing the rod 54 to move upwardly under the action of the spring 60. This motion retarded, however, as the air behind the piston 7 3' has to escape by the needle valve 81 the valve 80 has closed the passage 75. It will thus be seen that the lever 50 is quickly rotated in a clockwise .direction. This causes the rod 34 to be quickly moved downward, and then to gradually return it to its initial position, the amount which it is moved down being dependent entirely upon the position of the pin 56, as the rod 54 is always moved the sameamount, and the speed oi the return of the rod 34 is dependent upon the adjustment of the needle valve 81. hen the rod 34 moves downward, the strip 36 rapidly engages the contacts 44, 43, 42, 41 and 40, thus quickly closing the circuits through the terminals 29, 28, 27, 26 and 25. This causes the swell motor 21 to rapidly open the swell shutters 17, thus allowing the full volume of sound from the pipes 13, 14, 15, 16 to be emitted from the chamber 10.

As the rod 34 gradually moves upward, as previously described, the contacts 40, 41, 42, 43 and 44successively move off of the strip 36, thus breaking the circuits through the terminals 25, 26, 27, 28, 29 successively. This causes the swell shutters 17 to close .gradually under the action of the spring 19, thus slowly cutting down the amount of sound emitted from the chamber 10, which produces an eflect similar to that obtained by hit-ting a note in a piano, and holding the key down while the note gradually dies away. It will be seen from the foregoing description that when the key 90 is first depressed, the weight 110 will assume a position relative to the key 90. depending upon the speed with which the key is depressed, and this will determine the amount of current passing through the solenoid 95, which in turn determines the position of the pin 56. At the same time the rod 54 is moved downwardly, thus moving the rod 34 down wardly, the amount of motion being dependent upon the position of the pin 56. The amount that the rod 34 is moved downward, is therefore dependent upon the strength with which the key 90 is depressed, so that the volume of sound emitted from the chamber 10 will also be dependent upon the strength with which the key 90 is depressed. As the rate of decrease is constant, for any given adjustment of valve 81, the length of the note will be dependent upon how far the rod 34 is moved, which in turn is dependent upon the strength with which the key 90 is depressed.

lVhen the pressure on the key 90 is released it will assume its normal position under the action of the spring 92 thus breaking the circuits through the solenoids 95 and 66. The latter will allow the arm to be moved to its initial position under the ac tion of the spring 68 thus opening the valve 80 and allowing the rod 54 to be moved rapidly upward under the action of the spring 60. This causes the rod 34 to immediately assume its initial position thus rapidly closing the swell shutters 17. It will thus be seen that as soon as the finger is taken off the key 90 the sound of the note will be immediately stopped in the same manner as in a piano.

It will be noted that when the pressure onthe key 90 is released the contactor 107 Will move rapidly over the contacts 103 to 100, thus increasing the current through the solenoid 95, which will tend to move the rod 57 downwardly, thus tending to rotate the lever 50 in a counterclockwise direction about the pin 53. This will have no effect on the rod 34, however, as it will be al ready in its uppermost position.

In the modified l'orm shown in Figure 2 there'is provided an organ chamber 210 in which is mounted an organ chest 211. Within the chamber 210 and on the wind chest 211 is mounted an organ pipe 212 tuned to a predetermined note of a musical scale. The pipe 212 is preferably of the type which sounds only a pure fundamental note without any appreciable overtones such as the tuba series of pipes. It is understood that a chamber 210 and the pipe 212 is provided for each note of the musical scale within the range desired to be played. Positioned within each chamber 210' there is also provided a plurality of sub-chambers such as 213, 214, 215, there being three shown by way 01' example. l/Vithin each sub-chamber and communicating with the wind chest 211 there is provided an organ pipe 201, 202, 203, respectively. The pipe 203 is preterably tuned to the first harmonic of a fun damental note sounded by the pipe 212 and similarly, the pipes 202, 201 are tuned to additioi'ial upper harmonics thereof. In order that the sound produced by the pipes 201, 202. 203 may be suppressed or communicated to the interior of the chamber 210 as may be desired, one face of each of the subchambers is made movable. For example, the sub chamber 213 is provided with a hinged top 204 provided with a suitable bracket for a purpose which will be subsequently set forth. Similarly, the chamber 214 is provided with a hinged top 205 and the chamber 215 is provided with a hinged top 206. Each of the hinged tops is linked through a connecting rod to a swell motor of usual well known construct-ion. As shown, the hinged top 204 is connected to and actuated by a swell motor 220, the hinged top 205 to a swell motor 221 and the hinged top 206 to a swell motor 222. The

rod 34 is provided withstrips of" conducting material 35, 36 as in theembodiment shown in Figure 1 and also with additional strips of conducting material 223, 224,225, the strips 223 and 225 being mounted on an auxiliary rod 226 of insulating material which is rigidly secured to and carried by the rod 34. The brackets 37, 38 are spaced apart sufiiciently and the rod 34 is sufliciently long to provide for the additional contact strips.

The conducting strips 225, 224 and 223 are so positioned with respect to the conducting strip 36 that when the rod 34 is moved downwardly they engage their respective contacts successively, the arrangement being such that the contact strip 36 is the first one to make contact with any of its contacts, the'contact strip 225 making contact upon further movement of the rod 34, the contact strip 224 upon still further movcment oi the rod and the strip 223 only upon continued movement of the rod 34. The group of contacts engaged by the contact strip 225 extend to terminals of the swell shutter motor 220 for controlling the operation of the swell shutter 204 ot' the chamber 213. The groupoi contacts engaged by the contact strip 224 are connected to the terminals of the swell shutter motor 221 for controlling the operation of the swell shutter 205 of the chamber 214. Similarly the group of contacts engaged by the contact strip 223 are connectedto the terminals of the swell shutter motor 222, for controlling the operation of swell shutter 206 ot the chamber 215. Each of the group of contacts includes a battery supply con?- tact shown as the upper one of each series, which is connected throughthe battery 226 to the common return conductor 227. The common return conductor extends to suitable battery terminals of the swell shutter motor 222, 221 and 220. Thus when the rod 34 is moved downwardly the circuits of the swell shutter motor 220 are controlled for operating the swell shutter 204 to an extent dependent upon the downward movement of the rod 34. As is well known in the art, the extent of movement of swell shutter motors of this type depend upon the number 01 contacts of the respective group or control contacts, connected into circuit and as is evident from the present disclosure the number of such contacts to be closed is dependent upon the extent of down ward movement of the rod Similarly the extent oi movement of the swell shutter motor 221 andthe extentof opening of the swell shutter 205-v is dependent upon the movement of contacts oi the associated group. of contacts which are connected into circuit by the respective segment 224, and this is determined by the extent of downward (ill I tro-magnet 66.

movement of rod 34. It will also be seen that the initiation of the operation of the swell shutter motor 221 is subsequent to that of swell shutter motor 220. Snnilarly the extent or" movement of the swell shutter motor and the extent of opening of the swell shutter 206 is dependent upon the movement of contacts of the association group of contacts which are connected into circuit by the respective segment 223, and this is determined by the extent of downward movement of rod 34. It will also be seen that the initiation of the operation of the swell shutter motor 222 is subsequent to that of swell shutter motors 220 and 221. Thus the extent of downward movement of the rod 34 determines not only the extent of opening of the swell shutters 204, 205 and 206, but also determines how many of the said swell shutters are to be actuated.

For moving the arm 34 there is provided a floating lever having a slot 51 engaging a pin 52 aflixed to one end of the rod 34. The lever 50 is pivotally connected at a fulcrum 53 intermediate its length to a rod 54 extending substantially parallel to the rod 34. The lever 50 is provided at its other end with a slot 55 similar to the slot 51. The slot- 55 enga es a pin 56 ri idly secured to a movable solenoid core 57. uitable guides 59, 59 are providedfor the rod 54 and the solenoid core 57 to permit the respective longitudinal movement thereof. The cores 57 and 54 are normally maintained in the position shown by means of retractile springs 58 and 60 so affixed to one end of the cores 57 and 54 and to a portion of the frame work of the organ.

F or controlling the movement of the rod 54 there is provided therein a pin 61 in the path of movement of a finger 62. The fin ger 62 is pivotally supported upon one arm 63 of a bell-crank lever 64, the other arm 65 of which forms the armature of an elec- A retractile spring 68 is provided for maintaining the bell crank lever 64 in the position illustrated. The bellcrank lever 64 is pivotally supported in well known manner upon a fixed bracket extend ing outwardly fromv the frame of the electro-magnet 66. The finger 62 is provided with a lug 70and the bell-crank lever 64 is provided with an oppositely positoned like lug 71, there being interposed between the lugs 70 and 71 a retractile spring 67 for normally maintaining the finger 62 in the position shown. The finger 62 is provided with a stop member 72 integral therewith and arranged to engage the arm 63 to limit the retractile movement of the finger 62 relative to the arm 63.

' For retarding the movement of the rod 54 in one direction and for causing it to move at a predetermined speed after a working stroke, there is provided at its free end a 75 also communicates with an air inletcheck-valve 77 in one wall of the casing 74. One end of the passage 75is arranged to be opened and closed by a valve 80 connected to and operated by an armature 65 ofthe solenoid 66. The opposed end of the passage 75 is controlled by an adjustable needle valve 81 of usual construction the position of which with respect to the passage 75 determines the rate at which the air escapes :l'rom the cylinder of the dash-pot 74. The piston 73.is closely fitted within the cylinder and movement thereof in one direction is greatly restricted by the flow of air through the needle valve 81.,

For energizing the magnet 66 there is provided a circuit including a source of energy such as a battery 83, one pole of which is connected by means of a conductor 82 to one terminal of the winding of the magnet 66. The other pole of the battery 83 is connected by a conductorv 84 to a brush contactor 85 co-operating with a fixed contact 86 which in turn is connected by a con-ductor 87 to the other terminal of the winding of the magnet 66. The brush contactor 85 is fixed to and carried by a movable organ key 90 pivotally mounted at 91 and maintained in normal position by a retractile spring 92, .the retractile spring being attached to a fixed. member 93 secured to a portion of the frame work of the organ. The member 93 also serves as a stop member to limit the movement of the key 90. The arrangement is such that upon depression of the key 90 contact is closed between the contactor 85 and the contact 86 to close the circuit of the magnet 66. Thus the magnet 66 is energized to oscillate the bell-crank lever 64.

In order to limit the downward movement of the arm 34 so that its stroke is varied in accordance with the speed at which the key 90 is depressed, the core 57 is arranged to be actuated by a solenoid 95, one side of the winding of which is connected by a conductor 96 to the conductor 82, and the other side of the winding is connected by a conductor 97 to a variable resistance comprising a plurality of contact segments 100. 101, 102 and 103 arranged in series with resistance coils 104, 105, and 106. The contact segments are located in the arc of travel of a brush contactor 107 which is connected by conductor, 108 to the conductor 84 and thus to the other pole of the battery 83. Thebrush contactor 107 is carried by a weight 110 fixed to one end of an arm 111 having its opposite end pivoted at 112 to an extension 113 of the key 90. This extension 113 serves as a support at 114 for the arm 111, vandhas a toothed member 115 pivoted thereon and projecting upwardly in the path of a pin 116 on the arm 11.1. A spring 117 tends to rotate the member 115. counterclockwise and thusholds the toothed part in position to engage the pin 116 when the arm 111 is swung in a clockwise direction by the depression of the key 90. A pin 118 secured to a fixed part is provided which engages the toothed member 115 when the key 90 is in the position shown thus releasing the pin 116. p i

In the operation of theform of the invention shown in Figure 2, when it is desired to produce a musical note of the pitch to which the pipe 212 is tuned, the key .90 is depressed and the speed at which it is depressed determines the relative position to which the weight 110 is moved, thus, it the key 90 is depressed lightly and gently, the weight 110 will not change its position with respect to the key 90 and the conductor107 will rate on the segment 100 when the key 90 is fully depressed. If, however, the key 90 is depressed with greater speed, the mo mentum of the weight 110 will cause it to over-run the position of the key 90, thus moving the eontactor 107 into engagement with the segment 101. It will thus be seen that the contactor 107 will engage one of the segments 100 to 103, depending upon how fast the key 90 is depressed. When the key 90 is released andassumes the position shown in Fig. 1, under the action of the spring 92, the pin 118 will engage the member 115 and thus cause it to release the pin 116 which will allow the arm 111 and the weight 110 to assume their initial positions, as shown in Fig. 1, under the action of gravity. Suppose, for example, that the key 90 has been depressed with sufiicient speed to cause the contactor 107 to make contact with the segment 101. This will cause a current to flow from the battery 83 through the conductors84 and 108, contactor 107 segment 101, resistance 104, segment 100, conductor 97 and solenoid 95, conductors 96 and 82, back to the battery 83. This causes a definite amount of currentv to pass through the solenoid 95 and causes the core 57 to assume a definite position dependent upon the strength of this current and upon the strength of the spring 58. The pin '56 and therefore the left-hand end of the lever 50 will be moved into and held in a definite position. lVhen the key 90 is depressed, the contactor 85 engages the contact 86, thus closing the circuit through the magnet 66, which attracts the bell-crank lever 64, ro-

tating it about its pivot in a counter-clockwise direction. This causes the finger 62 to engage the pin 61, thus moving the rod 54 and the piston 73 downwardly. This motion is very rapid, as air enters thecheck valve 77. Before the bell-crank lever 64 has reached the end of its motion, the finger 62 has slipped out of engagement with the pin 61, thus allowing the rod 54 to move upwardly under the action of the spring 60. This motion is retarded, however, as the air behind the piston 73 has to escape by the needle valve 81 as the valve has closed the passage 7 5. It will thus be seen that the lever 50 is quickly rotated in a clockwise direction. This causes the rod 34 to be quickly moved downward, and then to gradually return it to its initial position, the amount which it is moved down being dependent entirely upon the position of the pin 56, as the rod 54 is always moved the same amount, and the speed of the return of the rod 34 is dependent upon the adjustment of the needle valve 81. lVhen the rod 34 moves downward, the strip 36 rapidly engages the contacts 44, 43, 42, 41 and 40. thus quickly closingthe circuits through. the terminals 29, 2 8, 27, 26 and 25. This causes the swell motor 21 to rapidly open the swell shutters 17, thus allowing the full volume of sound from the pipes 13, 14, 15 and 16 to be emitted from thechamber 10.

Supposing by way of example that the speed of downward movement of key 90 was such as to move the rod 34 downwardly to a suflicient extent so that the strip 225 engages only the upper two of the contacts oi the respective group of contacts A circuit will now be closed from the battery 226 upper contact of the groupof contacts associated with the contact strip 225, contact strip 225 in its displaced position second contact strip of the group terminal 240 of the swell shutter motor 220, swell shutter motor 220, common terminal 241 thereof, common conductor 22.7, to the opposite pole of the battery 226. The swell shutter motor 220 is actuated to a limited extent and causes the opening of the swell shutter motor 204 to arelatively small extent.

Thus the sound produced by the pipe 201 is emitted from the chamber 213 to a limited extent. The pipe 201. istuned to the second harmonic of the note produced by the pipe 212, and accordingly an added. quality is given to the music. V

Supposing now that the speed of downward movement of the key 90 is sufiiciently great so that the rod 34 is moved downwardly to a relatively greater extent, sufficiently to cause the contact strip 224 to engage the upper two contacts of its respective group of contacts. A circuit will then be closed from battery 226 upper contact of the group of contacts associated with the con-- (ill tact strip 224, contact strip 224 in its displaced position, second contact of the group terminal 241 of the swell shutter motor 221, swell shutter motor 221, common conductor 227 to the opposite pole of battery 226, thus the circuit of the swell shutter motor 221 and causing the same to be operated to a limited extent and opening the swell shutter 205 accordingly. Thus the sound produced by the pipe 202 is emitted from the chamber 214 to a limited extent. The pipe 202 is tuned to the third harmonic of the note produced by the pipe 212 and accordingly an added quality is given to the music.

It will be observed that when the rod 34 has been displaced to the extent just described, the strip 225 has engaged an additional contact of its respective group. Thus the respective swell shutter 204 is accordingly opened so as to increase the volume of sound emitted from the chamber 213. It will therefore be seen that when the third harmonic pipe 202 is sounded, the volume of sound emitted from the second harmonic pipe 201 is increased.

Let it now be assumed that the key 90 is depressed ata speed sufficient to move the rod 34 downwardly to a still greater extent. The strip 223 will now be brought into engagement with the upper two of its group of contacts and a circuit closed from the battery 226. The upper contact of the group of contacts associated with the contact strip 223, contact strip 223 in its displaced position the second contact of the group.'terminal 244 of the swell shutter motor 222, swell shutter motor 222 terminal 245 of the said swell. shutter motor, conductor 227 to the opposite pole of the battery 226. The swell shutter motor 220 is now operated to a limited extent and opens the swell shutter 206 accordingly. Thus the sound produced by the pipe 203 is emitted from the chamber 215 to a limited extent. The pipe 203 is tuned to the fourth harmonic of the note produced by the pipe 212 and accordingly an added quality is given to the music, and the strip 224 has also engaged an additional contact in its group so as to operate the swell shutter motor 221 still further.

It will be observed that when the rod 34 has been displaced to the extent just described, the strip 225 has engaged an additional contact of its respective group. Thus the respective swell shutter motors 220 and 221 are each operated to an additional extent and the swell shutters 204 and 205 are accordingly opened so as to increase the volume of sound emitted from the chambers 213 and 214. It will therefore be seen that when the fourth harmonic pipe 203 is sounded, the volume of sound emitted from the second and third harmonic pipes 201 and 202 is increased.

As the rod 34. gradually moves upwards under control of the needle valve 81, as has been described with reference to Figure l, the circuits of the several contacts are successively opened. This causes the swell shutters 17 toelose gradually under the action of the spring 19, thus slowly cutting down the amount of sound emitted from the chamber 210. Similarly the swell shutters 204, 205 and 206 are gradually closed, thus cutting down the sound emitted from the harn'ionic pipes 203, 202 and 201 successively. This action produces a novel musical effect and imparts an unusual quality to the music. The rate of movement of the rod 34 up wardly is substantially constant for any given adjustment of the valve 81 and the duration of time during which the quality imparted by the harmonics is dependent upon how far the rod 34 is moved, which in turn is dependent upon the manner in which the key 90 is depressed.

\Vhen the pressure on the key 90 is released, it will assume its normal position under the action of the spring 92, thus opening the circuits through the solenoids 95 and 06. The armature of the solenoid 66 will be restored to its initial position under the action of the spring 68, thus opening the valve 80 and allowing the rod 54 to be moved rapidly upward under the action of the spring 60. This causes the rod 34 to assume its initial position quickly, and thus the swell shutters 17, 204, 205 and 206 are rapidly closed. It will thus be seen that as soon asthe finger is taken from the key 90, the sound of the note will be quickly suppressed.

lVhen the pressure on the key 90 is re moved, the contactor 107 is rapidly restored to normal, and in passing over the contacts 103 to 100 the current through the solenoid 95 will be momentarily increased, but this will have no effect on the rod 34 as the rod 34 will be already in its uppermost position.

\Vhile I have shown and described two embodiments of my invention, it is understood that the scope of the invention is not to be limited thereby, reference being had to the appended claims for that purpose.

What I claim is 1. In an organ, a sound chamber, a pipe positioned within said chamber, means for causing said pipe to sound a musical note, an organ key, electric means actuated by depression of said key for operating said note producing means, a shutter for said sound chamber for varying the intensity of sound emitted from said chamber and a momentum device controlled by said key to actuate said shutter in varying degrees in accordance with the speed at which said key is depressed.

2. In an organ, a chamber, a pipe positioned within said chamber, means for causing said pipe to sound a musical note, an

organ key, electric means actuated by the depression of said key for operatingsaid note producing means, a shut er for said sound chamber including a momentum actuated device for controlling the intensity of sound emitted from said chamber and a momentum device controlled by said key to actuate said shutter in varying degrees in proportion to the speed at which said key is depressed.

3. In an organ, a sound chamber "for each note of the organ, a plurality of pipes positioned within said chamliier tuned to a respective note but each having a. dillerent musical tone, an organ key adapted to actuate said pipes to produce a musical note, a shutter in the wall of said chamber, means for variably opening'said shutter, and a momentum device operated by said key for controlling said shutter opeiatiiu;- means.

t. In an organ, a sound chamber for each note of the musical scale, a plurality of pipes for producing sounds of relatively difierent quality but tuned to the same note of the musical scale positioned in each of said sound chambers respectively, an organ key for each note of the musical. scale, means operatively interconnecting each of said keys to the respective pipes, a shutter for said sound chamber for variably controlling the emission. of sound therefrom, a motor for actuating said shutter and a momentun'i de vice associated with each of said keys and operated by the respective key in varying degrees in accordance withthe speed of movement of said key for operating said shutter motor in varying degrees.

5. The combination with a key, a member moved by said key and means for causing movement of said member varying with the speed of said key, of a sound chamber having positioned therein a plurality of. differently characterized sound producing elements actuated by movement of said key, and shutter mechanism for variably controlling the emission of sound from said chamber controlled by said member.

6. The combination with an organ key, an organ swell chamber having an opening, a

shutter normally closing said opening and t r, a motor for variably controlling said swell shutter to control the emission of sound from said chamber, and means operativcly interconnecting said momentum member and motor.

8. The combination with an organ key, an organ swell chamber having an opening, a

shutter normally closing said opening and a plurality of sound producing elements positioned within said chamber and actuated by said key, of a motor for actuating the Shutter, and an inertia controlled device variably operative under control of said key for controlling said motor.

Signed at Gloucester in the county of Essex and State of lilassachusetts this fifteenth day of August A. D. 1925.

JOHN HAYS HAMMOND, JR. 

